Branislav Sredanovic | University of Banja Luka (original) (raw)

Papers by Branislav Sredanovic

One of the most important factors in hard turning is tool wear, since tool condition affects the ... more One of the most important factors in hard turning is tool wear, since tool condition affects the quality of the product, tool life, and, consequently, the efficiency of the machining process. Modern methods of cooling and lubricating such is high pressure cooling provides possibility to reduce intensive wear of cutting tool due to better penetration of the fluid into the chip-tool and workpiece-tool interfaces. This paper investigates the potential of fuzzy expert system, where the fuzzy system is optimized using two bio-inspired algorithms, namely genetic algorithm (GA) and particle swarm optimization (PSO), for tool wear prediction in hard turning. Experiments have been conducted on a 100Cr6 (AISI 52100) steel workpieces with 62 HRC hardness using inexpensive coated carbide tools under high pressure cooling conditions. The estimated values of tool wear obtained from developed GA and PSO based fuzzy expert systems were compared with the experimental data and very good agreement was...

This paper describes the complete procedure for mathematical modeling of dynamic behavior of a sp... more This paper describes the complete procedure for mathematical modeling of dynamic behavior of a spindle holder – tool assembly. The developed model, in addition to translational, takes into account the rotational degrees of freedom, and therefore can be used for calculation and prediction of frequency response function of a spindle tool holder – tool assembly. In order to properly describe behavior of a dynamic system with correspondent mathematical model, including a spindle assembly, it is necessary, in addition to the exact mathematical model, to define unknown model parameters, i.e. different types of connections, which are very difficult, often impossible, to determine in the experimental way. Accordingly, this paper describes the mathematical formulation of the Levenberg-Marquardt method which was applied to identify the unknown parameters of a spindle assembly. In order to verify the proposed mathematical model of the spindle – holder – tool assembly and the principles for ide...

Lecture Notes in Mechanical Engineering

The increase of demands for products miniaturization has led to a need to research and explore th... more The increase of demands for products miniaturization has led to a need to research and explore the possibilities of micro-machining of special alloys. This paper presents the experimental study on the micro-milling of Inconel 718 super alloy. It is austenitic nickel-chromium based material which is oxidation resistant. Inconel 718 super alloy is used in the aerospace, automotive and energetic device industry. It applies for extreme environments subjected to high pressure and high temperatures. In this study, mentioned super alloy is machined with long neck micro-end-mill with diameter 0.6 mm, which is intended for side and channel milling of high aspect ratio features. The effects of cutting parameters on output machinability parameters were monitored. During experimental research, there are made conclusions about surface roughness, build-up on edges, cutting forces and etc. For purposes of practical application, general indicative data, area of cutting parameter values, and guidelines for micro-machining of Inconel 718 are given.

2020 19th International Symposium INFOTEH-JAHORINA (INFOTEH)

In the present study, the effect and optimization of three cutting parameters, namely depth of cu... more In the present study, the effect and optimization of three cutting parameters, namely depth of cut, cutting speed and feed rate on the specific energy consumption in the face milling was investigated by using the Taguchi method. Experiments were carried out in dry condition as per Taguchi's L9 orthogonal array. The cutting parameters were optimized using signal-to-noise ratio, whereas analysis of variance was employed to determine the significance of the process parameters influencing the specific energy consumption. The results revealed that feed rate and depth of cut are the most significant parameters affecting specific energy consumption. The confirmation test is conducted at optimum cutting conditions and it is found that the Taguchi method was notably successful in the optimization.

Tribology in Industry

Machining of engineering metallic materials on micro-level is very complicated. Micro-milling wit... more Machining of engineering metallic materials on micro-level is very complicated. Micro-milling with solid tools, as one of microengineering technologies, is an acceptable process to machining of complex metallic micro-parts. The main problem in micro-milling is sensitivity of cutting tool, due its suppleness and short tool life, and its influences to workpiece accuracy and quality. In this paper is experimentally investigated tool wear of micro-milling tool. During machining tests, influence of workpiece hardness and process parameters is evaluated. Workpiece was cold work alloyed tool steel X155CrVMo12, hardened to different hardness 45, 54 and 63 HRc. Cutting tool was carbide ball-end micro-mill with TiAlN coating, and diameter of 0.6 mm. For different combination of input parameters, tool wear curves is presented, and signification of input parameters on tool wear is evaluated and discussed.

Tribology in Industry

High Pressure Jet Assisted Machining (HPJAM) in turning is a hybrid machining method in which a h... more High Pressure Jet Assisted Machining (HPJAM) in turning is a hybrid machining method in which a high pressure jet of cooling and lubrication fluid, under high pressure (50 MPa), leads to the zone between the cutting tool edge and workpiece. An experimental study was performed to investigate the capabilities of conventional and high pressure cooling (HPC) in the turning of hard-to-machine materials: hard-chromed and surface hardened steel Ck45 (58 HRc) and hardened bearing steel 100Cr6 (62 HRc). Machining experiments were performed using coated carbide tools and highly cutting speed. Experimental measurements were performed for different input process parameters. The cooling capabilities are compared by monitoring of tool wear, tool life, cooling efficiency, and surface roughness. Connection between the tool wear and surface roughness is established. Experimental research show that the hard turning with carbide cutting tools and HP supply CLF provides numerous advantages from the techno-economic aspect: greater productivity, reduce of temperature in the cutting zone, improved control chip formation, extended tool life, low intensity of tool wear, surface roughness in acceptable limits, significant reduce of production costs related to the CLF.

Transactions of FAMENA, 2016

In this paper, machinability of turned steel defined by monitoring of cutting forces, tool wear, ... more In this paper, machinability of turned steel defined by monitoring of cutting forces, tool wear, surface quality and chip shape is presented. Experimental investigations were performed on untreated carbon steel C45E (hardness 45 HRc) and on surface induction hardened steel C45E (surface layer hardness 58 HRc). The analysis of machinability was performed under different cooling and lubrication conditions: conventional flooding, minimum quantity lubrication (MQL) and a hybrid machining method, i.e. high pressure jet assisted machining (HPJAM). The investigation was carried out for higher values of processing parameters. The results show the advantages of the advanced cooling and lubricating techniques, i.e. an increase in productivity and a reduction in production costs. The analysis of the results shows that the application of HPJAM gives superior machinability. Beside excellent chip breakability achieved in HPJAM, especially in hardened steel machining, significant improvement in tool life and reduction in cutting forces can be achieved.

Journal of Production Engineering, Dec 1, 2017

The objective of this study is to identify optimum machining parameters on surface quality of scu... more The objective of this study is to identify optimum machining parameters on surface quality of sculptured parts. The effect of various machining process parameters such as machining strategy, feed, depth of cut and spindle speed on surface roughness during three-axis end milling of sculptured parts have been studied by performing a number of experiments constructed according to standard Taguchi's L9 orthogonal array design matrix. Grey relational analysis method was used to find the optimal machining process parameters and analysis of variance was carried out to find the significance and contribution of each machining parameter on performance characteristics. Finally, confirmation test was conducted to indicate the effectiveness of this proposed method.

Applied Computing and Informatics

Sustainable manufacturing is one of the most important and most challenging issues in present ind... more Sustainable manufacturing is one of the most important and most challenging issues in present industrial scenario. With the intention of diminish negative effects associated with cutting fluids, the machining industries are continuously developing technologies and systems for cooling/lubricating of the cutting zone while maintaining machining efficiency. In the present study, three regression based machine learning techniques, namely, polynomial regression (PR), support vector regression (SVR) and Gaussian process regression (GPR) were developed to predict machining force, cutting power and cutting pressure in the turning of AISI 1045. In the development of predictive models, machining parameters of cutting speed, depth of cut and feed rate were considered as control factors. Since cooling/lubricating techniques significantly affects the machining performance, prediction model development of quality characteristics was performed under minimum quantity lubrication (MQL) and high-pres...

Proceedings on Engineering Sciences

Development of micro-devices parts is intensified with developments in medical device and energet... more Development of micro-devices parts is intensified with developments in medical device and energetic industry. In production of micro-parts (micro-pump, micro-gears, micro-manipulators, etc.), a wide range of engineering materials is encountered. Strict requirements are set in terms of characteristic of micro-parts machined surfaces, such are low surface roughness, advanced tribological characteristic, etc. In this paper is analysed possibilities of different metallic materials mechanical micro-machining. The analysis includes the analysis of the generating and characteristics of the machined surfaces, and influence of a whole set of parameters on surface characteristic. The results showed the benefits of mechanical micromachining and proved that it can achieve satisfactory results of the surface characteristics indicators.

Transactions of the Canadian Society for Mechanical Engineering

With the development of high-performance CNC machine tools, milling has been established as one o... more With the development of high-performance CNC machine tools, milling has been established as one of the main means of machining thin-walled parts. Thus, the selection of process parameters for milling operations is an important issue in end milling of thin-walled parts to assure product quality and increase productivity. The current study explores three machining parameters, namely wall thickness, feed, and machining strategies, that influence dimensional and form errors, surface roughness, and machining time milling of 7075-T6 aluminum alloy thin-walled parts. The effects of machining parameters on each of the response variables were analyzed using graphs of the main effects and three-dimensional surface plots. Analysis of the results show that the most influential factor for wall thickness deviation, dimensions deviation, perpendicularity deviation, flatness deviation, surface roughness of inner walls, surface roughness of outer walls, and surface roughness of reference plane was m...

Key Engineering Materials, 2016

The development of industry in the last ten years has caused the production of parts with relativ... more The development of industry in the last ten years has caused the production of parts with relatively small dimensions. This has led to intensive development of efficient micro-technologies through research of processes, machines and tools. This paper presents the research of machinability, channels micro-milling in AISI D2 tool steel (X155CrVMo-5), hardened to 62 HRc. As the tool is used micro-milling cutter with diameter of 0.6 mm and relatively large working length of 5 mm. Analysis of surface roughness, burr on workpiece edges and reduction of cutter diameter due tool wear was performed.

Strojarstvo Casopis Za Teoriju I Praksu U Strojarstvu, Apr 30, 2012

2011-10-10 Prihvaćeno (Accepted):

Development of new technologies encourage development of new materials, tools and cutting fluids ... more Development of new technologies encourage development of new materials, tools and cutting fluids and lubricants, and it is based on the development of flexible processing systems whose characteristics can respond to specific demands in production. Studies of interaction between machining system as whole unit and the quality of products are a complex tasks, where the definitions of machinability have an important role. Since the machinability of materials is most often defined by resistance to cutting, tool wear and surface quality, the goal of developing a new approach is to defining the universal machinability. Vector of machinability is the vector sum from vectors of criteria which defines machinability. During the research machinability under this approach, software for automatic definition and comparison of materials based on Vector of machinability is developed.

Journal of the Balkan Tribological Association

Rapid development of technologies encourages development of new materials, cutting tools, machine... more Rapid development of technologies encourages development of new materials, cutting tools, machine tools and cutting fluids and lubricants. Definitions of machinability have an important role, because it depends a number of influencing factors, primarily associated with mechanical, structural and thermal characteristics of working material and it is expressed through output parameters from machining process. During the research of machinability is developed a new approach in defining universal machinability based on vector analysis of parameters and software for automatic definition and comparison of materials. Output from this software can be used by manufaturers.

Definitions of machinability have an important role in material machining and it is defined by di... more Definitions of machinability have an important role in material machining and it is defined by different criterions. Some material may have a good machinability according to one criterion, but very low when the other criteria is considered. In this paper, using a new model for defining universal machinability by vector analysis is presented. Using this model will be able to define the material machinability by two or three criteria simultaneously. Experimental researches are performed and results are compared with other models. Also, this paper presents the impact of the application of modern techniques of cooling and lubrication fluids, to increase of productivity of machining processes.

This paper provides an analysis of the project of production system for the production of tools f... more This paper provides an analysis of the project of production system for the production of tools for hydraulic press brakes with application of production process simulation. The analysis is based on modeling and simulation of the process planning design for tools for hydraulic press brakes, with application of Experimental Manager module within the program system Tecnomatix Plant Simulation. Computer simulation shows the results of a working of production system and with interacting actions of designer it was achieved more balanced production and increased the effectiveness of the production system design.

Strojarstvo

This paper describes the complete procedure for mathematical modeling of dynamic behavior of a sp... more This paper describes the complete procedure for mathematical modeling of dynamic behavior of a spindle - holder – tool assembly. The developed model, in addition to translational, takes into account the rotational degrees of freedom, and therefore can be used for calculation and prediction of frequency response function of a spindle - tool holder – tool assembly. In order to properly describe behavior of a dynamic system with correspondent mathematical model, including a spindle assembly, it is necessary, in addition to the exact mathematical model, to define unknown model parameters, ie. different types of connections, which are very difficult, often impossible, to determine in the experimental way. Accordingly, this paper describes the mathematical formulation of the Levenberg-Marquardt method which was applied to identify the unknown parameters of a spindle assembly. In order to verify the proposed mathematical model of the spindle – holder – tool assembly and the principles for ...

One of the most important factors in hard turning is tool wear, since tool condition affects the ... more One of the most important factors in hard turning is tool wear, since tool condition affects the quality of the product, tool life, and, consequently, the efficiency of the machining process. Modern methods of cooling and lubricating such is high pressure cooling provides possibility to reduce intensive wear of cutting tool due to better penetration of the fluid into the chip-tool and workpiece-tool interfaces. This paper investigates the potential of fuzzy expert system, where the fuzzy system is optimized using two bio-inspired algorithms, namely genetic algorithm (GA) and particle swarm optimization (PSO), for tool wear prediction in hard turning. Experiments have been conducted on a 100Cr6 (AISI 52100) steel workpieces with 62 HRC hardness using inexpensive coated carbide tools under high pressure cooling conditions. The estimated values of tool wear obtained from developed GA and PSO based fuzzy expert systems were compared with the experimental data and very good agreement was...

This paper describes the complete procedure for mathematical modeling of dynamic behavior of a sp... more This paper describes the complete procedure for mathematical modeling of dynamic behavior of a spindle holder – tool assembly. The developed model, in addition to translational, takes into account the rotational degrees of freedom, and therefore can be used for calculation and prediction of frequency response function of a spindle tool holder – tool assembly. In order to properly describe behavior of a dynamic system with correspondent mathematical model, including a spindle assembly, it is necessary, in addition to the exact mathematical model, to define unknown model parameters, i.e. different types of connections, which are very difficult, often impossible, to determine in the experimental way. Accordingly, this paper describes the mathematical formulation of the Levenberg-Marquardt method which was applied to identify the unknown parameters of a spindle assembly. In order to verify the proposed mathematical model of the spindle – holder – tool assembly and the principles for ide...

Lecture Notes in Mechanical Engineering

The increase of demands for products miniaturization has led to a need to research and explore th... more The increase of demands for products miniaturization has led to a need to research and explore the possibilities of micro-machining of special alloys. This paper presents the experimental study on the micro-milling of Inconel 718 super alloy. It is austenitic nickel-chromium based material which is oxidation resistant. Inconel 718 super alloy is used in the aerospace, automotive and energetic device industry. It applies for extreme environments subjected to high pressure and high temperatures. In this study, mentioned super alloy is machined with long neck micro-end-mill with diameter 0.6 mm, which is intended for side and channel milling of high aspect ratio features. The effects of cutting parameters on output machinability parameters were monitored. During experimental research, there are made conclusions about surface roughness, build-up on edges, cutting forces and etc. For purposes of practical application, general indicative data, area of cutting parameter values, and guidelines for micro-machining of Inconel 718 are given.

2020 19th International Symposium INFOTEH-JAHORINA (INFOTEH)

In the present study, the effect and optimization of three cutting parameters, namely depth of cu... more In the present study, the effect and optimization of three cutting parameters, namely depth of cut, cutting speed and feed rate on the specific energy consumption in the face milling was investigated by using the Taguchi method. Experiments were carried out in dry condition as per Taguchi's L9 orthogonal array. The cutting parameters were optimized using signal-to-noise ratio, whereas analysis of variance was employed to determine the significance of the process parameters influencing the specific energy consumption. The results revealed that feed rate and depth of cut are the most significant parameters affecting specific energy consumption. The confirmation test is conducted at optimum cutting conditions and it is found that the Taguchi method was notably successful in the optimization.

Tribology in Industry

Machining of engineering metallic materials on micro-level is very complicated. Micro-milling wit... more Machining of engineering metallic materials on micro-level is very complicated. Micro-milling with solid tools, as one of microengineering technologies, is an acceptable process to machining of complex metallic micro-parts. The main problem in micro-milling is sensitivity of cutting tool, due its suppleness and short tool life, and its influences to workpiece accuracy and quality. In this paper is experimentally investigated tool wear of micro-milling tool. During machining tests, influence of workpiece hardness and process parameters is evaluated. Workpiece was cold work alloyed tool steel X155CrVMo12, hardened to different hardness 45, 54 and 63 HRc. Cutting tool was carbide ball-end micro-mill with TiAlN coating, and diameter of 0.6 mm. For different combination of input parameters, tool wear curves is presented, and signification of input parameters on tool wear is evaluated and discussed.

Tribology in Industry

High Pressure Jet Assisted Machining (HPJAM) in turning is a hybrid machining method in which a h... more High Pressure Jet Assisted Machining (HPJAM) in turning is a hybrid machining method in which a high pressure jet of cooling and lubrication fluid, under high pressure (50 MPa), leads to the zone between the cutting tool edge and workpiece. An experimental study was performed to investigate the capabilities of conventional and high pressure cooling (HPC) in the turning of hard-to-machine materials: hard-chromed and surface hardened steel Ck45 (58 HRc) and hardened bearing steel 100Cr6 (62 HRc). Machining experiments were performed using coated carbide tools and highly cutting speed. Experimental measurements were performed for different input process parameters. The cooling capabilities are compared by monitoring of tool wear, tool life, cooling efficiency, and surface roughness. Connection between the tool wear and surface roughness is established. Experimental research show that the hard turning with carbide cutting tools and HP supply CLF provides numerous advantages from the techno-economic aspect: greater productivity, reduce of temperature in the cutting zone, improved control chip formation, extended tool life, low intensity of tool wear, surface roughness in acceptable limits, significant reduce of production costs related to the CLF.

Transactions of FAMENA, 2016

In this paper, machinability of turned steel defined by monitoring of cutting forces, tool wear, ... more In this paper, machinability of turned steel defined by monitoring of cutting forces, tool wear, surface quality and chip shape is presented. Experimental investigations were performed on untreated carbon steel C45E (hardness 45 HRc) and on surface induction hardened steel C45E (surface layer hardness 58 HRc). The analysis of machinability was performed under different cooling and lubrication conditions: conventional flooding, minimum quantity lubrication (MQL) and a hybrid machining method, i.e. high pressure jet assisted machining (HPJAM). The investigation was carried out for higher values of processing parameters. The results show the advantages of the advanced cooling and lubricating techniques, i.e. an increase in productivity and a reduction in production costs. The analysis of the results shows that the application of HPJAM gives superior machinability. Beside excellent chip breakability achieved in HPJAM, especially in hardened steel machining, significant improvement in tool life and reduction in cutting forces can be achieved.

Journal of Production Engineering, Dec 1, 2017

The objective of this study is to identify optimum machining parameters on surface quality of scu... more The objective of this study is to identify optimum machining parameters on surface quality of sculptured parts. The effect of various machining process parameters such as machining strategy, feed, depth of cut and spindle speed on surface roughness during three-axis end milling of sculptured parts have been studied by performing a number of experiments constructed according to standard Taguchi's L9 orthogonal array design matrix. Grey relational analysis method was used to find the optimal machining process parameters and analysis of variance was carried out to find the significance and contribution of each machining parameter on performance characteristics. Finally, confirmation test was conducted to indicate the effectiveness of this proposed method.

Applied Computing and Informatics

Sustainable manufacturing is one of the most important and most challenging issues in present ind... more Sustainable manufacturing is one of the most important and most challenging issues in present industrial scenario. With the intention of diminish negative effects associated with cutting fluids, the machining industries are continuously developing technologies and systems for cooling/lubricating of the cutting zone while maintaining machining efficiency. In the present study, three regression based machine learning techniques, namely, polynomial regression (PR), support vector regression (SVR) and Gaussian process regression (GPR) were developed to predict machining force, cutting power and cutting pressure in the turning of AISI 1045. In the development of predictive models, machining parameters of cutting speed, depth of cut and feed rate were considered as control factors. Since cooling/lubricating techniques significantly affects the machining performance, prediction model development of quality characteristics was performed under minimum quantity lubrication (MQL) and high-pres...

Proceedings on Engineering Sciences

Development of micro-devices parts is intensified with developments in medical device and energet... more Development of micro-devices parts is intensified with developments in medical device and energetic industry. In production of micro-parts (micro-pump, micro-gears, micro-manipulators, etc.), a wide range of engineering materials is encountered. Strict requirements are set in terms of characteristic of micro-parts machined surfaces, such are low surface roughness, advanced tribological characteristic, etc. In this paper is analysed possibilities of different metallic materials mechanical micro-machining. The analysis includes the analysis of the generating and characteristics of the machined surfaces, and influence of a whole set of parameters on surface characteristic. The results showed the benefits of mechanical micromachining and proved that it can achieve satisfactory results of the surface characteristics indicators.

Transactions of the Canadian Society for Mechanical Engineering

With the development of high-performance CNC machine tools, milling has been established as one o... more With the development of high-performance CNC machine tools, milling has been established as one of the main means of machining thin-walled parts. Thus, the selection of process parameters for milling operations is an important issue in end milling of thin-walled parts to assure product quality and increase productivity. The current study explores three machining parameters, namely wall thickness, feed, and machining strategies, that influence dimensional and form errors, surface roughness, and machining time milling of 7075-T6 aluminum alloy thin-walled parts. The effects of machining parameters on each of the response variables were analyzed using graphs of the main effects and three-dimensional surface plots. Analysis of the results show that the most influential factor for wall thickness deviation, dimensions deviation, perpendicularity deviation, flatness deviation, surface roughness of inner walls, surface roughness of outer walls, and surface roughness of reference plane was m...

Key Engineering Materials, 2016

The development of industry in the last ten years has caused the production of parts with relativ... more The development of industry in the last ten years has caused the production of parts with relatively small dimensions. This has led to intensive development of efficient micro-technologies through research of processes, machines and tools. This paper presents the research of machinability, channels micro-milling in AISI D2 tool steel (X155CrVMo-5), hardened to 62 HRc. As the tool is used micro-milling cutter with diameter of 0.6 mm and relatively large working length of 5 mm. Analysis of surface roughness, burr on workpiece edges and reduction of cutter diameter due tool wear was performed.

Strojarstvo Casopis Za Teoriju I Praksu U Strojarstvu, Apr 30, 2012

2011-10-10 Prihvaćeno (Accepted):

Development of new technologies encourage development of new materials, tools and cutting fluids ... more Development of new technologies encourage development of new materials, tools and cutting fluids and lubricants, and it is based on the development of flexible processing systems whose characteristics can respond to specific demands in production. Studies of interaction between machining system as whole unit and the quality of products are a complex tasks, where the definitions of machinability have an important role. Since the machinability of materials is most often defined by resistance to cutting, tool wear and surface quality, the goal of developing a new approach is to defining the universal machinability. Vector of machinability is the vector sum from vectors of criteria which defines machinability. During the research machinability under this approach, software for automatic definition and comparison of materials based on Vector of machinability is developed.

Journal of the Balkan Tribological Association

Rapid development of technologies encourages development of new materials, cutting tools, machine... more Rapid development of technologies encourages development of new materials, cutting tools, machine tools and cutting fluids and lubricants. Definitions of machinability have an important role, because it depends a number of influencing factors, primarily associated with mechanical, structural and thermal characteristics of working material and it is expressed through output parameters from machining process. During the research of machinability is developed a new approach in defining universal machinability based on vector analysis of parameters and software for automatic definition and comparison of materials. Output from this software can be used by manufaturers.

Definitions of machinability have an important role in material machining and it is defined by di... more Definitions of machinability have an important role in material machining and it is defined by different criterions. Some material may have a good machinability according to one criterion, but very low when the other criteria is considered. In this paper, using a new model for defining universal machinability by vector analysis is presented. Using this model will be able to define the material machinability by two or three criteria simultaneously. Experimental researches are performed and results are compared with other models. Also, this paper presents the impact of the application of modern techniques of cooling and lubrication fluids, to increase of productivity of machining processes.

This paper provides an analysis of the project of production system for the production of tools f... more This paper provides an analysis of the project of production system for the production of tools for hydraulic press brakes with application of production process simulation. The analysis is based on modeling and simulation of the process planning design for tools for hydraulic press brakes, with application of Experimental Manager module within the program system Tecnomatix Plant Simulation. Computer simulation shows the results of a working of production system and with interacting actions of designer it was achieved more balanced production and increased the effectiveness of the production system design.

Strojarstvo

This paper describes the complete procedure for mathematical modeling of dynamic behavior of a sp... more This paper describes the complete procedure for mathematical modeling of dynamic behavior of a spindle - holder – tool assembly. The developed model, in addition to translational, takes into account the rotational degrees of freedom, and therefore can be used for calculation and prediction of frequency response function of a spindle - tool holder – tool assembly. In order to properly describe behavior of a dynamic system with correspondent mathematical model, including a spindle assembly, it is necessary, in addition to the exact mathematical model, to define unknown model parameters, ie. different types of connections, which are very difficult, often impossible, to determine in the experimental way. Accordingly, this paper describes the mathematical formulation of the Levenberg-Marquardt method which was applied to identify the unknown parameters of a spindle assembly. In order to verify the proposed mathematical model of the spindle – holder – tool assembly and the principles for ...